How to get correct longitude and latitude using address in google maps

I am working with google map,

I got address, latitude, langitude from foursquare site,

that latitude and longitude are implemented in google map,

then display google map marker is wrong place,

How to get correct latitude and longitude using address

Try This
// get logitude and latitude
$address=$param['address'].', '.$param['city'].', '.$param['state'].', '.$param['country'];
$address = urlencode($address);
$json = file_get_contents("http://maps.google.com/maps/api/geocode/json...");
$decoded = json_decode($json, true);
if(isset($decoded['results'][0]['geometry']['location']['lat']) && isset($decoded['results'][0]['geometry']['location']['lng'])){
$param['latitude'] = $decoded['results'][0]['geometry']['location']['lat'];
$param['longitude'] = $decoded['results'][0]['geometry']['location']['lng'];
}else{
$param['latitude'] = '';
$param['longitude'] = '';
}
// end of longitude and latitude

Here is another code
/// get loaction through longitude and latidute
$url = 'http://maps.googleapis.com/maps/api/geocode/json...';
$json = file_get_contents($url);
$datas=json_decode($json);
$status = $datas->status;
if($status=="OK"){
$param['address'] = $datas->results[0]->address_components[0]->short_name.' '.$datas->results[0]->address_components[1]->short_name;
$param['city'] = $datas->results[0]->address_components[3]->long_name;
$param['state'] = $datas->results[0]->address_components[6]->short_name;
$param['country'] = $datas->results[0]->address_components[7]->short_name;
$param['zipcode'] = $datas->results[0]->address_components[8]->short_name;
}else{
$param['address'] = "";
$param['city'] = "";
$param['state'] = "";
$param['country'] = "";
$param['zipcode'] = "";
}

I use it, but that is display wrong location example : https://maps.google.com/maps... this link is display correct location, but you given link
URL: http://maps.google.com/maps/api/geocode/json...
Result is : latitude and longitude 51.51212289999999,-0.1335969 that latitude and longitude is wrong place display